Along with a critical security update for Windows Server, Microsoft has patched the Windows version of PowerPoint to overcome an important vulnerability. But where's the update for the same issue in PowerPoint for Mac?

May is shaping up to be a quiet month for systems administrators, at least as far as security patches from Microsoft are concerned. The company is also changing the way it indicates the importance of specific security updates.

Microsoft this week issued a dozen security bulletins addressing 22 vulnerabilities in Windows, Internet Explorer, Internet Information Service and Internet Explorer. The company also released a so-called non-security update that has everything to do with security.

We're nearly a week into the month, so it's time to find out what Patch Tuesday will bring. Unusually, Microsoft's listing no updates for any version of Windows, but there is an important patch for the recently released Office 2011 for Mac.

August's Patch Tuesday has seen the delivery of 14 security bulletins from Microsoft. More than half are rated critical, and a total of 34 vulnerabilities are addressed.

Microsoft has provided its customary advance notice of security bulletins, and it looks like August's Patch Tuesday is going to be a big one with a record 14 bulletins.

As foreshadowed, Microsoft released four security bulletins overnight. One affects Windows 7 and three are rated critical.

Next Tuesday will see the publication of four security bulletins from Microsoft, three of them rated critical.

March 2010's Patch Tuesday was, as anticipated, a low-key affair with just two bulletins. But Microsoft has also warned of new and publicly disclosed vulnerability that is being exploited in older versions of its Internet Explorer browser.

Microsoft has provided advance notification that two bulletins will be issued on this month's Patch Tuesday, addressing a total of eight issues.